


Control

by orphan_account



Series: Sanscest Uncommon-pairs [4]
Category: Undertale (Video Game)
Genre: Ecto-Genitalia (Undertale), Ecto-Penis (Undertale), Ecto-Tongue (Undertale), First Time, Loss of Virginity, M/M, Overstimulation, PWP, Strength Kink, a little mind control in the beginning
Language: English
Status: Completed
Published: 2019-09-16
Updated: 2019-09-16
Packaged: 2020-10-19 18:41:32
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,572
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20661908
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: Cross and Classic had been talking lately. It'd taken a while, but Cross was starting to see Classic as maybe a friend.One day, when they're alone in the woods, something strange happens.





	Control

It had all happened so suddenly. Cross had cracked a rare smile and laughed breathlessly at one of Classic’s jokes. Classic’s gaze had darted down to Cross’ mouth.

Then, Cross’ body had started moving on its own.

Internally, Cross was kind of freaking out. He searched his SOUL for any hint of Chara and his surroundings for any hint of Nightmare, Ink, or X!Gaster. But his old tormentors were nowhere to be found.

Cross’ mouth had fallen slack back into its usual frown and his eye sockets were strangely half-lidded. His body stepped forward and gently cradled Classic’s skull.

Cross had an awful premonition of what was about to happen next.

Sure enough, his body pressed his teeth to Classic’s. Classic also seemed surprised at this development, but he soon leaned into the kiss and obediently opened his mouth for Cross to enter.

_No, Classic! Don’t just go along with whatever this is! Help me! _Cross thought, panicked. It didn’t do anything.

Strangely enough, Classic seemed to be getting… really _into_ whatever was going on. He even let out a frankly pornographic moan that would have made Cross blush as dark as Nightmare if he’d had control of his body.

The two of them were standing in the middle of a forest with enormous trees. Classic took initiative, not that Cross was able to, to slam Cross’ back to a tree trunk. Whatever was keeping control over Cross loosened a bit with the sudden movement. Cross inwardly cheered.

But it wasn’t enough. Cross still didn’t have control back yet and Classic was leaning forward to deepen the kiss. A leg was thrust inbetween Cross’ legs, which made Cross want to immediately fall unconscious to not have to deal with the situation.

Cross couldn’t believe this was happening. He’d always thought Classic hated him. After all, Cross had butchered Classic’s SOUL, even if he hadn’t wanted to, and he’d had nothing but a lackluster apology to show for it.

However, that didn’t explain why Classic was getting so heated. Maybe he was under someone else’s control, too.

The thoughts Cross was having were rapidly knocked out of his skull as Classic set a surprisingly grueling pace. Classic grinded his knee into Cross’ pelvis in a firm and deliberate move that Cross just knew he was using to make him summon his magic.

Cross’ body was pliant, as if acting on instinct alone. A cock made of purple magic appeared beneath Classic’s knee before long.

Even though he had no control over his body, Cross still felt the pleasure from the deliberate movements on his cock. His body threw his head back and he agreed with the sentiment. _When did Classic get this forward?_

Classic tugged Cross’ shorts down to reveal his already dripping cock. Cross wanted to cover up again, but just resigned himself to losing all dignity.

Suddenly, Classic fell to his knees and brought his mouth right up next to Cross’ cock. Classic touched the hardened length with the tip of his tongue. A bead of precome traced its way down to settle on Classic’s tongue, making him shudder.

At the shudder, the control on Cross completely dropped away. Classic’s eye sockets widened and Cross wobbled a bit, trying to stay upright.

“Wh-wha…?” Cross mumbled awkwardly. “Classic…?”

“Aha…” Classic somehow managed to blush even brighter than before. He averted his eye-lights and smiled sheepishly, a move that Cross privately thought was adorable. “I—I can explain—”

Cross leaned back against the tree trunk to stabilize himself. He’d had no idea he could feel so good. He didn’t know if he could keep calm if Classic didn’t leave soon.

“... I have the power to control the bodies of the other versions of us,” Classic admitted. “But I don’t know that I’m doing it until I lose the control, honest! I thought you wanted to…”

It was actually a huge relief that Classic had been the one controlling Cross, but he didn’t get the chance to express this before Classic was bowing his head in shame. His skull dragged down Cross’ member.

“Hnn—!” Cross let out an involuntary noise, squeezing his eye sockets shut.

When Cross finally forced his eye sockets back open, he saw that Classic still had his soft cheekbone pressed up against his cock. The look on Classic’s face was something like shock.

“I-it’s okay, you didn’t mean it…” Cross muttered. “I’m used to these sorts of things happen—ahh—!”

Classic moved his skull backwards, rubbing his cheek back up Cross’ member in what was probably an accidental move. Cross had to steady himself again.

“You’re… really sensitive.” Classic whispered, eye-lights dilated.

“Hah…” Cross panted. “I… haven’t really done anything like this before. I mean, I know how… sex works, but I’ve never even touched myself before…” He trembled out of nervousness.

Classic’s mouth was opened a little in a cute “o” shape. But this cute look quickly shifted to something more seductive. His eye sockets went half-lidded and his eye-lights glowed brighter.

“Hey, Cross…” Classic said. “You look like you want something… is it okay if I _take care of _you?”

Cross immediately got the implications of the question and went completely purple. “O-okay…” He’d never thought it’d be _Classic_ of all people to ask something like this.

Classic hovered over Cross’ cock and flicked his tongue at the slit of it.

“A-aahh—!” Cross slipped a foot down the tree trunk because his legs were shaking so much.

Classic swiftly reacted. He gripped Cross’ femurs near the pelvis with the strong grip befitting a Royal Judge. With Cross suspended in the air, Classic put his mouth properly on Cross’ cock and sucked the head of it into his mouth.

Cross’ vision sparkled with stars. All he could do was put his hands on Classic’s shoulders and take the onslaught as Classic slurped around his cock.

“C-Classic…!” Cross cried softly. Tears sprang to the corners of his eye sockets. “I think so-something’s—”

The heat building up in Cross’ pelvis rapidly grew as Classic’s glowing, blue tongue wriggled out of his mouth and around the length of Cross’ cock. Classic then swallowed hard.

“Class—ic…!” Cross choked out as he came into Classic’s mouth. Classic swallowed after each spurt of come and after he’d drank it all, he licked Cross’ cock to get any remaining fluid off.

“Ah… hah…” Cross scrabbled at Classic’s shoulders until he slowed down. Cross looked absolutely wrecked with his mouth open and his eye-lights unfocused. Tears rolled down his cheekbones at the overstimulation he’d received.

Classic brought his head up from between Cross’ legs while licking his mouth clean. He then lapped the tears off of Cross’ cheeks and kissed him, shoving his tongue into his mouth.

After they broke the kiss, Classic spoke. “Heh, I get it now. You’re a sub…”

“... Or maybe I’ve just never had sex before…” Cross muttered, irritated even though he knew it was just a joke.

Cross ground his pelvis down into Classic’s cock. Cross’ magic hadn’t yet dissipated, so it gave delicious friction to Classic’s cock through the smooth fabric of Classic’s shorts. Classic groaned.

The friction on Cross’ still oversensitive cock made him have to suppress a shudder. He arched his back against the tree trunk and slung his right arm around Classic’s back to press them close together. The position made his summoned hole rub up against Classic’s clothed cock. Cross brought a hand down to rectify that, slipping Classic’s shorts down and letting his cock bob out in the open.

These actions all happened in less than a second. Classic gasped and looked to be restraining himself from pushing deep into Cross.

Cross wrapped his legs around Classic’s waist and thrust them together as hard as he could. Classic’s cock was sheathed down to the hilt.

“A-ah!” Classic rested his head on Cross’ left shoulder. “W-wait, you need to be stretched!”

There was pain in Cross’ abdomen, but it wasn’t like he hadn’t felt much worse before. He just needed Classic to come to assuage it.

Cross squeezed around Classic’s cock and started riding him as best he could. He went fast and hard, sending lots of magic down to his hole to lubricate it, if only for Classic’s benefit.

Classic wasn’t deterred for long, though. He did tremble and nuzzle into Cross’ neck, but he still tried to pull himself out of Cross.

“N-no, you’ll get hurt…” Classic couldn’t say any more. His attempts to fend off the harsh pace were ineffective.

Classic was already close, so all Cross had to do was clench once more for a thick and hot stream of come to enter him. Classic bit down on Cross’ clavicle.

They stayed still for a couple seconds. Then Cross’ legs went loose, letting Classic finally drag his cock out in a wave of come. Cross hissed in pain before he could stop himself.

**“****... You’re hurt.****”** Classic growled. Cross shivered as he instantly recognized the tone of the multiverse’s most powerful Judge. Even after coming, Classic still held Cross up with ease.

“It doesn’t hurt.” Cross said. He managed not to stutter even with the Judge speaking right next to his skull.

Classic pushed a finger into Cross’ hole and crooked it. Cross breathed as evenly as he could through the sharp stinging along his walls, but a particularly painful area made him inhale sharply enough for the Judge to notice.

Classic lapped at the bite mark on Cross’ clavicle soothingly. Soon after, all the pain ebbed away, to be replaced by a sweet warmth. Cross relaxed into the hold, realizing Classic was using healing magic.

Suddenly, the finger inside of Cross pulsed with healing magic and sent it through his whole pelvis. He jerked and gave a little moan at the unexpected stimulation.

The Judge caressed Cross’ walls and healed them until Cross was writhing on his finger and crying again. Classic also grabbed Cross’ cock with his other hand, supporting Cross against the tree with gravity magic instead. The combined stroking of his cock and magic tingling through him made Cross’ cock, which had softened, hard again.

The finger reached in deeper than before to hit Cross’ prostate. It had more injuries than the other areas, so Classic channeled more healing magic than before.

Cross whimpered. He was quickly falling apart again.

“C-Classic, please…!” Cross whined.

**“****I'm going to make you feel good.****”** The Judge purred. **“****Over and over. Now come for me.****”**

Cross came, unable to resist the smooth voice of the strongest Judge. Classic’s skilled hands eased him through it.

“P-please…” Cross said hoarsely. “Please fuck me, Sans…!”

He felt Classic twitch at the usage of their real name. Classic prodded his finger in with more force than necessary, which Cross knew was to check if he was still injured or not. Cross keened and shifted his hips downwards in a display of need.

Classic took his hands off of Cross and hugged them around him to hold him up instead of using gravity magic. Cross wrapped his legs behind Classic’s back again.

**“****I’ll be leading this time.****”** Classic murmured with his cheek still pressed against Cross’ neck. **“****No more getting hurt.****”**

Classic entered Cross slowly and gently. Cross could do nothing but shake at the feeling of it, so much better than before.

It seemed to take hours for Classic to sheathe himself. Halfway through, Cross couldn’t stand the slow and teasing pace anymore and tried to move his hips, but Classic tightened his grip on Cross’ pelvis and growled a little.

Cross obediently stilled himself, but it was difficult. It was more difficult than being a slave to Nightmare and X!Chara ever was.

Finally, Classic bottomed out, the tip of his cock touching Cross’ prostate, just nudging it. Cross had to focus on breathing slower and deeper to keep his attention from the torturously slow pace.

After a minute, when Cross could hardly stand the wait any longer, Classic began to pull out. Beginning to move again brought an exhale out of relief, but the terribly slow pace made each moment of a cock dragging along his walls stand out all the more.

A rhythm started. The steady in and out of Classic’s thrusts was unbearably soft. It was almost worse than the pain from before; Classic was being so… _gentle_. It was unlike anything Cross had ever experienced before.

“Hhh…!” One of Classic’s thrusts came more sharply than the others, bumping Cross’ overstimulated prostate.

At this, Classic actually _slowed down_. When this occurred, Cross realized that he had to beg or they’d be at it for hours more.

“... Classic…” Cross murmured.

For once, Classic drew back enough that Cross could see his face. His eye-lights were dark in his half-lidded eye sockets and his smile was small and sharp. There was something predatory about his gaze.

“Please…” Cross sighed. He wasn’t smiling. There was a desperate expression on his face.

“I’m not letting you **get hurt again.****”** Classic’s voice started out normal, but rapidly went dangerous once more.

Cross ran his hands down Classic’s back, if only just to watch him relax like a wildcat.

“I’m not made of glass.” Cross said. Classic looked like he was about to interrupt based on the narrowing of his eye sockets, but Cross continued. “I want you to be rough with me. I _want_ you to go fast and hard. I want the pain. I don’t want you to hold yourself back anymore.”

Classic stared at him for a long moment.

Then, he jabbed his cock at Cross’ prostate sharply.

“Hahh…” Cross managed to keep himself from wincing and instead pulled Classic’s head towards his own to meet in a kiss.

Classic began thrusting faster. He also thrust his tongue into Cross’ mouth, devouring it.

Cross took the opportunity to cant his hips into Classic’s thrusts. When Classic’s hands tightened around his pelvis again, almost painfully, Cross used gravity magic and forced him to go faster.

Classic’s magic fought back for control, but Cross squeezed his walls around Classic’s cock and hugged him closer to himself. Cross was already close, so he sped the pace up ever faster.

Classic broke off the kiss to bury his face in Cross’ neck, whimpering quietly. Cross grinned.

Cross was almost there. A few more harsh rolls against his prostate and he’d spill his come out against Classic’s hoodie. So, Cross sent magic down into his pelvis and stimulated Classic’s cock with his magic just as Classic had done with healing magic earlier. Cross was a quick learner.

“Nn!” Classic muffled a noise by biting Cross’ clavicle again.

Warm, magic-filled come flooded Cross’ insides. It gushed against his prostate, unable to leak out because of Classic’s cock plugging up the hole. Cross came from the sensation with a weak cry.

As soon as Classic recovered, he immediately stood up straight again, inadvertently shifting his cock and causing Cross to shudder.

“Are you okay?” Classic asked, panicked. His expression had completely changed with the thought of him hurting Cross.

“Yeah…” Cross mumbled sleepily. Classic didn’t look reassured, so he tried again. “Tired…”

Classic’s expression softened. “I’ll bring you back to your house.”

“Nn… stay with me…”

“Okay.” Classic smoothed his hand down the back of Cross’ skull.

Cross gave one of his rare smiles, warm and sincere. “... Love you…”

Classic’s eye sockets and eye-lights widened. He hugged Cross tight.

“Love you, too.”

**Author's Note:**

> So Cross is unrealistically sensitive here, but come on. They're magic skeletons. Just chalk it up to magic skeleton magic.  
Also, they're in a forest because it's a pwp and I say so.
> 
> Last of the finished ones from a year ago, but there are a couple more that I left almost finished.


End file.
